Adjustable supports for fourdrinier screen wires



H. E. DUNLAP April 3, 1962 ADJUSTABLE SUPPORTS FOR FOURDRINIER SCREEN WIRES 2 Sheets-Sheet 1 Filed Dec.

INVENTOR HAROLD E. DUNLAP 6Mf&

ATTORNEY April 1962 H. E. DUNLAP 3,027,940

ADJUSTABLE SUPPORTS FOR FOURDRINIER SCREEN WIRES Filed Dec. 51, 1958 2 Sheets-Sheet 2 INVENTOR HAROLD E. DUNLAP ATTORNEY vof the wire in advance of the rolls.

Engineering Corporation, Worcester, Mass, a corporation of Massachusetts Filed Dec. 31, 1958, Ser. No. 784,133 8 Claims. ((1 162-352) This invention relates to new and improved adjustable supporting means for the wires or screens of Fourdrinier machines in the paper-making industry, and the principal object of the present invention resides in the provision of a novel support which not only supports the wire or screen much more efficiently than either the wedges or the rolls of the prior art, but also obtains and enhances the advantages of both rollers and wedge-type deflectors which are used for supporting the screen or wire in the prior art.

The horizontal screen wire of the Fourdrinier machine travels at a relatively high rate of speed from the breast roll to the couch roll, and the water tends to drip down through the screen so that the poper pulp on the wire gradually condenses. The screen wire requires support, and the prior art has used so-called small table rolls, or deflectors in the nature of wedges provided with flat tops and beveled edges facing the direction of travel of the wire. These wedges tend to scrape off the bottom of the wire and the rolls being rotated by the wire, develop a slight vacuum at the rear portion thereof with respect to the passage of the wire thereover, and this helps to suck the water from the wire. There are well known objections to both of these devices. The rollers must be dynamically balanced, and are apt to deflect, being supported at their ends only. This allows the wire to sag across the face of the machine. Also, water temporarily adhering to the rolls is often flung back to the under sides The rollers may tend to clog the wire. The wedges are not provided with any natural suction means such as occurs with the use of the rollers and if the wire sags between supports, the sharp front edge of the wedge may abrade the wire.

It is the primary object of the present invention to combine the advantages .of wedges and rolls of the prior art without the disadvantages of the same, in a single deflector unit which is adjustable in such a way that it may be provided with a convexly curved top edge surface over which the Fourdrinier screen wire passes in contact therewith, so that the new deflector provides the scraping action at the leading edge and the vacuum action at the following edge thereof, and in addition to which the degree of curvature of the new deflector may be varied to suit conditions so as to derive the optimum of support and water extraction as may be possible, and which is not possible with the deflectors and rolls of the prior art.

Other objects and advantages of the present invention reside in the provision of means for tilting the new deflector in a direction toward the breast roll so as to adequately support the screen wire, regardless of any sag which may be imparted just after the breast roll; and the provision of means for both tilting the entire device and adjusting the arc of the same to accommodate any condition which may be encountered in a Fourdrinier wire; and the provision .of means for adjusting the tilt from a remote position without stopping the machine in any way, such adjustment being capable of being made instantly and to any degree desired within the range of the device, by the operator of the machine while the same is in operation or at rest.

The invention further relates to arrangements and combinations of parts which will be hereinafter described and more particularly set forth in the appended claims.

Reference is to be had to the accompanying drawings, in which:

FIG. 1 is a view in side elevation illustrating a Fourdrinier wire with the new deflectors applied thereto, parts being in section;

FIG. 2 is an enlarged rear elevational view looking in the direction .of arrow 2 in FIG. 1, parts being broken away;

FIG. 3 is a view on an enlarged scale illustrating in greater detail one of the deflectors of FIG. 1;

FIG. 4 is a view similar to FIG. 3, showing the deflector in a different adjusted position;

FIG. 5 is a view similar to FIG. 4 showing another adjustment;

FIG. 6 is a view illustrating a Fourdrinier wire with a modified form of the invention applied thereo; and

FIGS. 7 and 8 are enlarged views illustrating the deflectors shown in FIG. 6 and the manner of adjusting the same.

In carrying out the present invention, the Fourdrinier screen wire is generally indicated at 10 and it is to be understood that this is a more or less diagrammatical representation of the wire, breast roll 12, and couch roll 14. The wire 10 is endless as is well known in Fourdrinier machines, and the reference numeral 16 illustrates the framework which may be applied or which is already existing in different form and set-ups of Fourdrinier machines as is well known in the art. This framework appears at both sides of the machine and it is to be understood that the Fourdrinier wire may be of any width desired and of any length commensurate with industrial applications.

In any event, the present new deflectors may be mounted across the machine and under the wire as for instance directly behind the breast roll on a framework which is generally indicated by the reference numeral 13. This framework may be mounted on the framework 16 and extends transversely across the machine as indicated, the particular mounting means not being critical to the present invention. However, brackets 20 appearing at both ends of framework 18 may be clamped in any desired way to the frameworks 16 and in this case the brackets are shown as being provided with flanges 22 secured as for instance by bolt clamp assembly 24 to the framework 16 which in this case has a horizontal portion or flange 26. If desired, the brackets 20 may be tilted by proper adjustment of screw-threaded fasteners 28, 30 for a purpose to be described, but in any event, it is seen that the frameework 18 extends transversely of the screen wire and under the same and may be mounted as desired at its ends or otherwise with respect to the framework of the Fourdrinier machine.

The framework 18 is provided at spaced intervals with vertical webs indicated at 32, there being as many of these as may be desired or convenient, and they may be utilized to support among other things, threadedly adjustable stop pins 34* and a plate member 36 which extends from side-to-side of the machine as is indicated in FIG. 2. This transverse member 36 is fixed to or may be an integral part of a forwardly extending transverse member 38 which terminates at 4% in a wedge or point, the purpose of which will be explained more fully hereinafter.

Also, the transverse members 36 and 38 are integral with or fixed with respect to a rearwardly extending transverse member 42 overlying and spaced from member 36 but shorter than the latter and being provided with a beveled edge or the like 44. The member 42 and its edge 44 of course extends along the entire width of the machine, and the member 36 has at its rearward edge upstanding flange portion 46.

The transverse member 26 acts as a shelf-like support for a pair of hoses which are indicated at 48 and S0 respectively. These hoses are adapted to be provided with air or other fluid under pressure, source of which is not here shown but which may be of conventional design and provided with conventional valves, safety devices, etc., so that either hose 48 or hose 50 may be placed under pressure or both of them may be relieved of the internal fluid pressure. Resting on the two hoses, as perhaps more clearly indicated in FIG. 3, there is a transverse rigid plate 52 which is not fixed or even secured. to any other part of the machine but which has as a fulcrum point the pointed edge 44 of the overlying member 42. When air hose 48 for instance is provided with pressure as indicated in FIG. 4, the plate 52 rocks in a clockwise direction; on the other hand, when hose 50 is provided with pressure and hose 48 is deleted, the plate 52 then rocks in the opposite direction about a longitudinal axis, the fulcrum being provided by the longitudinal edge 44. This action is illustrated in FIG. 5, and it is seen therefore that the angular position of plate 52 is under control of the operator at all times because of the fact that the air hoses may be provided with conventional air supply, valves, etc. at a side of the machine.

The bearing surface or board supporting the screen wire it) is also a laterally extending plate-like member extending transversely across the machine directly under the wire 10. This member is preferably provided with a smooth surface in a member which is indicated at 54. It has been found that a modified form of Teflon is a suitable substance for this member as it forms a natural bearing surface and the wire slides rapidly over the same with a minimum of flutter, noise and wear. However, any other suitable material may be utilized particularly one which is easily formed or shaped by the wire itself to the desired conformation as required by the natural travel of the wire.

In the situation illustrated, the entire board is formed of flexible material and the underlying member 56 upon which the bearing member 54 is mounted may be brass, steel, or any suitable metal, or it may be of plastic, reenforced or otherwise, etc., and it is provided at each end with a wedge-shaped element, these being indicated at 58 at the forward end and at 60 at the rearward end thereof. The members 54 and 56 are likewise beveled as clearly shown in FIGS. 3 and 4 in order to provide the wedge or inclined areas 62, 64 which act somewhat in the manner of the prior art deflector edge or wedge and which may be applied to the lower surface of the Fourdrinier screen to scrape the same as is illustrated in both FIGS. 3 and 4.

The parts so far described are arranged so that when both hoses 48 and 50 are devoid of interior pressure, the board comprising the members 54 and 56 is substantially horizontal and flat and thus may be used in this position to support the screen wire at any position along its length where a flat board is required. However, by inflating hose 48, the rear edge portion of the board is required to descend as shown in FIG. 4 by forcing plate 52 in a clockwise direction. Plate 52 bears in the corner provided by the beveled surface at 66 of the wedge part at 60 and thus forces the entire rear portion of the board down to a degree determined by the setting of the adjustable stop pins 34.

By this manipulation of the device, it will be seen that an extremely long are of great radius may be provided at the rear side of the support as the wire passes over it, and this forms an extremely eflicient suction device for extracting the fluid through the wire from top to bottom in a greatly improved action over that of the usual relatively small diametered table roll. It will be seen that not only is the scraping action at the forward end of the device under constant control so that an optimum scraping action is provided, but also an optimum natural vacuum or suction is provided at the rear edge of the deflector, so that the new deflector accomplishes the functions. of both the wedges and rolls of the prior art and improves these functions while doing away with the disadvantages inherent in the wedges and table rolls of the prior art.

If, on the other hand, it is desired to tiit the board in the opposite direction, this is accomplished by exhausting pipe 48 and applying pressure to pipe 50, with the result as seen in FIG. 5 that the board is tilted in a forward direction, and the reason for the projection of the forward member at 46 into the notch provided at 68 by the wedge member 58 Will now be apparent, as this forms a fulcrum or support for the tilting action of the entire board. The stops 34 may or may not be adjusted to maintain this position as seen in FIG. 5, but in any event not only is the board adjustable, from the position of FIG. 3 to the position of FIG. 4, but also if desired to a loading position as seen in FIG. 5.

In addition to the above, of course the entire support may be tilted forward and back by means of the stop members 28 and 30 as illustrated in FIG. 1 upon loosening of the clamp 24 and re-application of pressure thereto in 'a manner which will be clear to those skilled in the art.

FIGS. 6, 7 and 8 illustrate a modified construction which is generally the same in mounting and tilting arrangement as above stated and described. However, in the construction of FIGS. 6 to 8 inclusive, the framework is here indicated at St), the web members at 82, the stops at 84, and in this case the web members support at their top ends a transverse continuous plate 86 which acts as an upper stop for the hose 88. The hose may be enclosed in a channel member 90 which is secured by a fastener as at 92 to a spring plate also extending laterally of the machine as indicated at 94. The spring plate is securely fastened at 96 to a supporting member 98 which is provided with a forwardly-extending wedge 100 engaged in the notch in the wedge member 192 which may be otherwise similar to that at FIG. 8.

The spring plate 94 continues past the channel member 90 as is shown at 14M and is engaged in the notch 106 of the rear wedge member 108 which may be otherwise similar to that at 60 and of course the board itself at 110 may be, if desired, similar to that at 54 or 56.

The operation of this form of the invention will be equally clear. The hose 88, when pressure is applied thereto, brings the spring plate 94 in a clockwise direction about the point 96 as a fulcrum and thus draws the board 114 downwardly as shown in FIG. 6 to support the screen Wire here indicated at 112 as above stated, and the reverse adjustment is accomplished by the spring 94 itself moving back to its original position upon the exhaustion of air or pressure in hose 88.

There is often a sag in the screen wire, this being indicated in FIG. 6 or 114, this sag for instance being present after the wire moves from the breast roll 12. The present deflector provides for a clear, adequate support of this portion of the Wire, and also tilting the board forwardly provides a tangent contact against the curve of sag of the device, thus reducing any tendency for the sharp bevel of board to tear or excessively abrade the wire. In this case, the forward wedge at 102 is depressed slightly to accommodate the sag at 114, and of course depending upon the conditions and the desire of the operator, the board may be provided with its arced conformation as described above. The board may be made substantially flat if desired as in FIG. 7 for better support of the wire at any particular location. This sag effect may be taken care of by either or both modifications as shown in this invention, and it will be seen that the construction of FIG. 1 may be tilted forwardly by tilting of the entire bracket as illustrated with the same reference numerals in FIG. 6, it being pointed out that the flange 22 in FIG. 2 and the flange 116 in FIG. 6 are equivalents.

In further explanation of the drawings in this case,

particularly with reference to FIGS. 1 and 6, it is pointed out that the breast roll 12 and the couch roll 14 usually have a diameter within a range of twenty to forty inches, whereas the total heights of the deflector construction would be approximately from eight to ten inches. However, the drawing has been made as shown in order to more clearly illustrate the invention, particularly with reference to the details of construction of the new and improved deflectors herein.

Also, as in the usual Fourdrinier machine, the wire is provided with suction boxes as for instance at A in FIG. 1, the doctor blade as at B in FIG. 1, pans or the like to collect the white water as at C, and a water shower or the like D as well as wire return rolls of which there are generally five as illustrated at E.

Having thus described my invention and the advantages thereof, I do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claims, but what I claim is:

1. The combination of a deflector and the screen wire of a Fourdrinier machine, said deflector comprising a support, a flexible board on the support, said board being arranged relative to the Fourdrinier wire to have a leading edge and a trailing edge, and means to adjustably flex said board in a direction to present an arc-shaped supporting conformation to the screen wire with the leading edge of the board in contact with the screen wire.

2. The combination of a screen wire of a Fourdrinier machine and a support for the wire comprising a flexible board, said board extending under the wire transversely of the direction of travel of the wire, said board being arranged relative to the Fourdrinier wire to have a leading edge and a trailing edge, and means to adjustably flex said board in a direction to present an arcshaped supporting conformation to the screen wire, said flexing means comprising a plate-like member loosely engaged with said board at the trailing edge thereof and means for adjustably inclining said plate-like member on an axis transverse to the direction of travel of the wire with the leading edge of the board in contact with the under side of the screen wire.

3. The combination of a screen wire of a Fourdrinier machine with a deflector, a support, a flexible board on the support, said board extending under the wire transversely of the direction of travel of the wire, said board being arranged relative to the Fourdrinier wire to have a leading edge and a trailing edge, and means to adjustably flex said board in a direction to present an arcshaped supporting conformation to the screen wire, said flexing means comprising a plate-like member loosely engaged with said board at the trailing edge thereof and means for adjustably inclining said plate-like member on an axis transverse to the direction of travel of the wire, with the leading edge of the board in contact with the under side of the screen wire, said plate-like member being rigid.

4. In a Fourdrinier machine having a screen wire, a deflector comprising a support, a flexible board on the support, said board extending under and in contact with the wire transversely of the direction of travel of the wire, and means to adjustably flex said board in a di rection to present an arc-shaped supporting conformation to the screen wire, said flexing means comprising a platelike member loosely engaged with said board and means for adjustably inclining said plate-like member on an axis transverse to the direction of travel of the Wire, said plate-like member being in the form of a spring having two ends, said spring being anchored at one end and freely engaging the board at the opposite end.

5. In a Fourdrinier machine having a screen wire, a deflector comprising a support, a flexible member mounted on said support, means on said support for positively flexing said member to present an arc-shaped supporting conformation to the screen wire, said means comprising a movable plate, and a fluid pressure inflatable hose associated with said plate to cause distortion of the plate under influence of pressure in said hose.

6. In a Fourdrinier machine having a screen wire, a deflector comprising a support, a flexible member mounted on said support, means on said support for positively flexing said member to present an arc-shaped supporting conformation to the screen wire, said means comprising a movable plate, and a fluid pressure inflatable hose associated with said plate to cause distortion of the plate under influence of pressure in said hose, said plate loosely mounted on said support.

7. In a Fourdrinier machine having a screen wire, a deflector comprising a support, a flexible member mounted on said support, means on said support for positively flexing said member to present an arc-shaped supporting conformation to the screen wire, said means comprising a movable plate, and a fluid pressure inflatable hose asso ciated with said plate to cause distortion of the plate under influence of pressure in said hose, said plate being in the form of a spring having an end, said spring being anchored at said one end.

8. In a Fourdrinier machine having a screen wire, a deflector comprising a support, a pair of inflatable hoses on said support, a plate supported on said hoses and means forming a fulcrum for said plate, said plate being otherwise unsecured, the fulcrum being located laterally between the hoses so that when either hose is provided With pressure and the other hose is exhausted, the plate is adapted to tilt, a supporting flexible board, said plate being interconnected with a part of said board adjacent an edge thereof, and means for supporting said board in another remote position whereby when said plate is inclined under influence of said hoses, said supporting member is deflected on the arc of a curve.

References Cited in the file of this patent UNITED STATES PATENTS 2,170,109 Berry Aug. 22, 1939 2,372,248 Bouton Mar. 27, 1945 2,477,339 Ljungquist July 26, 1949 2,694,345 Hornbostel Nov. 16, 1954 2,744,454 Wagenknecht May 8, 1956 2,858,746 Goodwillie Nov. 4, 1958 2,861,541 I-Iornbostel Nov. 25, 1958 FOREIGN PATENTS 399,739 Great Britain Oct. 12, 1933 717,798 Great Britain Nov. 3, 1954 786,998 Great Britain Nov. 27, 1957 328,826 Switzerland May 14, 1958 

